RecyclerView (FirestoreRecyclerOptions)在活动的onCreate中显示为已填充，但在按下back按钮时为空

// 导入所需的类
import com.google.firebase.firestore.FirebaseFirestore;
import com.google.firebase.firestore.Query;
import com.firebase.ui.firestore.FirestoreRecyclerOptions;
import com.firebase.ui.firestore.FirestoreRecyclerAdapter;

// 在活动的onCreate方法中
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    // 创建RecyclerView实例并设置布局管理器
    RecyclerView recyclerView = findViewById(R.id.recyclerView);
    recyclerView.setLayoutManager(new LinearLayoutManager(this));

    // 创建FirestoreRecyclerOptions实例并配置查询条件和排序规则
    Query query = FirebaseFirestore.getInstance().collection("your_collection");
    FirestoreRecyclerOptions<YourModelClass> options = new FirestoreRecyclerOptions.Builder<YourModelClass>()
            .setQuery(query, YourModelClass.class)
            .build();

    // 创建FirestoreRecyclerAdapter实例并设置为RecyclerView的适配器
    FirestoreRecyclerAdapter<YourModelClass, YourViewHolder> adapter = new FirestoreRecyclerAdapter<YourModelClass, YourViewHolder>(options) {
        @Override
        protected void onBindViewHolder(@NonNull YourViewHolder holder, int position, @NonNull YourModelClass model) {
            // 在这里绑定数据到ViewHolder中的视图
        }

        @NonNull
        @Override
        public YourViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
            // 在这里创建ViewHolder并返回
        }
    };
    recyclerView.setAdapter(adapter);
}